#include <stdio.h>

int leap_year(int x)
{
    return ((x%4 == 0 && x%100 != 0) || (x%400 == 0));
}
int main()
{
    int y = 0;
    printf("请输入一个年份：");
    scanf("%d", &y);
    if(leap_year(y) == 1)
        printf("是素数");
    else
        printf("不是素数");
    return 0;

}